Mailcellar copies every message from your mail accounts into ordinary .eml files you own. Read them offline, search them instantly, and see which senders are tracking you — without anything leaving your Mac.
Free · macOS 14+ · Apple silicon & Intel · ~3 MB · How to open it the first time
Mailcellar is a mail archive first: it never sends mail and never changes your mailbox unless you ask it to free up space.
Pick folders per account and press Back Up Now, or let it run every few hours while the app is open. Only new messages are downloaded each time.
Stored as Account/Folder/Year/date subject id.eml in Documents. Open them in Apple Mail, Outlook or Thunderbird — no lock-in.
A local index of subjects, people and body text. Results appear as you type; save any search as a smart filter.
Remote images stay off until you allow them. Hidden 1×1 pixels and known tracking services are counted and blocked even then.
Shows the SPF, DKIM and DMARC results your provider recorded, warns when replies would go to another domain, and flags links whose text names a different site.
Every attachment listed with its size. Preview with Quick Look or save it anywhere.
Bring in .eml files and .mbox exports (for example from Google Takeout) so everything lives in one searchable archive.
Sign in with an app-specific password; it’s kept in your macOS Keychain. Connections always use TLS. No accounts with us, no cloud.
Choose a folder and a date. Mailcellar checks every older message against your archive before anything is removed from the server.
A message only counts as safe when its local .eml exists, is exactly the size the server reports, and opens as a valid email. You see the summary, type a confirmation, and only those verified messages are deleted. Anything else stays on the server.
Providers like Google, Apple, Yahoo and Fastmail let you create a separate password for a single app. Mailcellar uses it to sign in over IMAP, and the add-account screen walks you through making one for each provider. You can revoke it at any time without changing your main password.
It can, if your Microsoft account still accepts app passwords for IMAP. Microsoft has been moving personal accounts to OAuth-only sign-in, which Mailcellar doesn’t support yet.
Backups only read: folders are opened read-only and messages are fetched without marking them as read. The server is only changed when you run Free Up Space and confirm it.
In Documents/Mailcellar by default (you can pick another folder in Settings), as one .eml file per message. The search index sits next to it in a hidden folder.
Yes. Mailcellar is a backup and reader, not a mail client — it doesn’t send mail.
Mailcellar is distributed directly from this website. Here’s how to open it the first time.
Add an account, pick folders, press Back Up Now.